[media] cx25840: more cx23888 register address changes

The cx23888 also moves the following registers around:

!cx23888	cx23888
--------	-------
0x418, 0x41c	0x434, 0x438
0x420		0x418 (expect for bit 29 which has a different meaning)
0x478		0x454

Also drop the set_input code where the scaler is changed: this does not
belong here, changing the input should not change the scaler.

And that's besides the fact that that code is plain wrong.

After this change the cx23888 behaves much better. In particular, calling
set_input no longer changes the saturation to 0, causing a grayscale
image.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>